In 2006, Google introduced a Java application called Google Maps for Mobile, intended to run on any Java-based phone or mobile device. Many of the web-based site's features are provided in the application.

On November 28, 2007, Google Maps for Mobile 2.0 was released. It introduced a GPS-like location service that does not require a GPS receiver. The "my location" feature works by utilizing the GPS location of the mobile device, if it is available. This information is supplemented by the software determining the nearest wireless networks and cell sites. The software then looks up the location of the cell site using a database of known wireless networks and cell sites. The Cell-site location method is used by triangulating the different signal strengths from different cell transmitters and then using their location property (retrieved from the online cell site database) to aid My Location in determining the user's current location. Wireless network location method is calculated by discovering the nearby WiFi hotspots and using their location property (retrieved from the online WiFi database, in the same way as the cell site database) to further discover the user's location. The order in which these take precedence is:

The software plots the streets in blue that are available with a yellow icon and a green circle around the estimated range of the cell site based on the transmitter's rated power (among other variables). The estimate is refined using the strength of the cell phone signal to estimate how close to the cell site the mobile device is.

 #http://en.wikipedia.org